1. Field of the Invention
The present invention relates to an electrical connector, and in particularly to a battery connector having improved retaining force.
2. Background of the Invention
Disk-shaped cells or batteries are often used as back up protection for electronic equipment should there be a failure in the conventional power system. Typically, these disk-shaped backup cells are relatively small, having, for example, a diameter of about 0.268 inches and a thickness of about 0.083 inches. The cell has a positive electrode extending along a major surface and the edge and a negative electrode extending over the other major surface and isolated from the positive electrode. For purposes of this invention the term “battery” is to be understood to include a single cell. The battery is inserted into a connector mounted to a circuit board, the connector hereinafter being referred to as a “battery connector”. It is desirable that a backup battery connector be easy to mount to the circuit board, be readily accessible for replacing a depleted battery, and be cost effective to manufacture.
Taiwan Patent No. 291187 (referred to as the '187 patent for short) issued on Nov. 11, 1996 discloses a battery connector for holding a coin battery therein. Referring to FIGS. 1 to 5 in the '187 patent, the battery connector in which the coin battery 20 is retained includes an insulative battery holder 10 and a positive contact 14 vertically received in a bottom near a side of the insulative battery holder 10. The positive contact 14 has a fastener 15 disposed at a side of a slightly upper portion thereof and extending inwardly. The fastener 15 has a sloped surface in a top edge thereof, and a protruding tab 16 extending outwardly is connected with a top end of the fastener 15. The positive contact 14 includes a resilient tab 17 disposed a back side thereof and extending outwardly for leaning against a blocking wall 12 of the insulative battery holder 10. Especially with reference to FIG. 5, when the battery 20 is removed from the battery connector, it is required to pull the protruding tab 16 outwardly by hand, whereby the battery 20 is disengaged from the fastener 15. Because the positive contact extends in a vertical direction and it is necessary to control a whole height of the battery connector, the positive contact 14 can't be longer so that deformation of the positive contact is focused on a small scope, thereby causing stress of the positive contact to be concentrated overly and further causing the positive contact is easily subject to be deformed permanently. Furthermore, a distal end of the resilient tab 17 is against the bottom of the insulative battery holder so as to restraint deformation of a lower portion of the positive contact, whereby stress of the positive contact is further concentrated in a smaller scope of an upper portion of the positive contact, possibly resulting in breakage of the positive contact due to excess deformation.
It is thus desirable to provide a battery connector that alleviates and even overcomes the above disadvantages.